Electric furnace.



No. 897,203. PATENTED AUG. 25, 1908.

J. HARDEN. I

V ELECTRIC FURNACE APPLICATION FILED MAY 8, 1908.

2 SHEETS-SHEET 1.

UNITED STATES PATENT oEEicE.

JOHANNES HARDEN, or LONDON, ENGLAND, ASSIGNOR TO THE oRoNDAL KJELLIN ooMPANY.

LIMITED, OF LoNDo ENGLAND.

ELECTRIC FURNACE.

' Specification of Letters Patent.

Patented Aug. 25, 1908.

Application filed. May 8, 1908. Serial No. 431,707.

To all whom it may concern:

Be it known that I, JOHANNES HARDEN, a subject of the King of Sweden, residing at 20 Abchureh Lane, in the city of London, England, have invented certain new and useful Improvements Relating to Electric Furnaces,

of which the following is a specification.

the whole furnace and auxiliary plant is rendered idle until the new lining is ready for.

use, and consequently the economy of the furnace is considerably impaired. To overc'ome this defect it has been proposed to use a primary windingcommon to two or more fusion chambers, so that said winding serves as the primary for any one of the chambers while one ormore of the remainder are being repaired. Such an arrangement, however,

necessitates the two or more fusion chambers being made definite parts of the furnace. The chief object of the present invention is to obviate the disadvantages above stated.

According to this invention the furnace is provided with a removable hearth or lining, so that when repairs become necessary the furnace charge may be run off into a ladle or other contrivanee and contained therein while a fresh hearth or llmng is being substituted for the defective one. I The lattermay then be repaired at leisure.

In orderthat the said invention may be clearly understood and readily "carried into effect, I will describe the same more fully with reference to the accompanying drawings, in which Figures 1 and 2 are elevations taken at right angles to eachother, and Fig. 3 is a vertical section in dotted lines of one form of furnace constructed according to this invention. Fig. 4 is a vertical longi tudinal section through a furnace constricted according to the present invention, a tilting support bemg shown in connection therewith.

A is the central limb or core of an 1ron frame closed upon itself, the said core having the primary coil of the furnace wound thereon, and B is the bed or framework on which the furnace stands.

C is the annular fusion chamber in which the charges are placed.

The hearth or lining D is built or stamped in a metallic or other suitable casing E, which is independent of the other parts of the furnace and attached to the main body or framework thereof in any appropriate manner, as for example by bolts E.

The casing E maybe provided with lifting hooks F or other appropriate means so that it, together with the hearth or liningD, can be lifted from the body of'the furnace (as shown in dotted lines in Fig. 3) by means of a crane or otherwise, and a spare one put in its place without any appreciable delay, thus greatly increasing the working efiiciency of the furnace and itsauxiliary plant.

Then a damaged hearth orlining is about to be removed, the molten material in it may be transferred to a ladle, gas heated furnace, or other contrivance for keeping the mate rial hot, and contained therein during the act of substituting a spare casing and lining; the said molten material may then be run into the spare lining and thus obviate the necessity of restarting the furnace by means of iron rings as-is now usual, but is objectionable owing to the tendency of the said rings to break. The spare casing with its lining 4 may be heated, previous to the transference ofthe molten material from the gasheated furnace or other contrivance, by :means of coke, gas-jets, or charcoal, and thus prevent the temperature of the lining from becoming changed too suddenly. 'By the use of re-' movable hearths or linings as hereinbefore described, great economy in working is obtained as regards time, labor and material, and the'output of'the plant ismaterially increased. v

What I claim and desire .to secure by Letters Patent of the'United States is z 1. In an electric induction furnace, an iron frame, a primary'coi lpositioned thereon, an annular fusion chamber surrounding one limb of said frame, a housing for said fusion chamterio; peri fixery thereof, a pair of braces s:

on: l to said housing and acting as supports 15 therefor, a tilting su sport, means for securing 7 said 'lirs'b in ntioneo supports rigidly to said and from said frame. tilting support, and means for removing said 2. In an electrical induction furnace, an housing and said fusion chamber when said her, movable support for supygwrting i f i l l 11011 name, a primary eon mounted. thereon, securing meai'is have been removed. 20

housing, means for securing sair housing to said support, and means for removing .illd

housnn and fusion chamber ofi said su". nor-t an annular fusion chamber surrounding one i In testimony whereof I allix my signature lllnl) of said frame, a housing for said fusion in presence of two Witnesses. chamber, an angle iron surrounding: the up JOI'IANNES HARDEN. per edge of said housing for bracing the same, angle irons surr unding said housing on the. lower edge thereof upon the exterior and in- Witnesses:

Geo. ii. lZE sEY, Eimes'r H. ROBERTS. 

